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Format(3)                        OCaml library                       Format(3)




NAME

       Format - Pretty printing.


Module

       Module   Format


Documentation

       Module Format
        : sig end


       Pretty printing.

       This module implements a pretty-printing facility to format text within
       'pretty-printing boxes'. The pretty-printer breaks lines  at  specified
       break hints, and indents lines according to the box structure.

       For a gentle introduction to the basics of pretty-printing using Format
       , read http://caml.inria.fr/resources/doc/guides/format.en.html.

       You may consider this module as providing an extension  to  the  printf
       facility   to   provide   automatic  line  breaking.  The  addition  of
       pretty-printing annotations to your regular printf  formats  gives  you
       fancy  indentation  and  line  breaks.  Pretty-printing annotations are
       described below in the documentation of the function Format.fprintf .

       You may also use the explicit box  management  and  printing  functions
       provided by this module. This style is more basic but more verbose than
       the fprintf concise formats.

       For instance, the sequence open_box 0; print_string x =  ;  print_space
       ();  print_int  1;  close_box  ();  print_newline  () that prints x = 1
       within a pretty-printing box, can be abbreviated as printf @[%s@ %i@]@.
       x = 1 , or even shorter printf @[x =@ %i@]@. 1 .

       Rule of thumb for casual users of this library:

       -use simple boxes (as obtained by open_box 0 );

       -use  simple  break  hints  (as obtained by print_cut () that outputs a
       simple break hint, or by print_space () that outputs a space indicating
       a break hint);

       -once  a  box is opened, display its material with basic printing func-
       tions (e. g.  print_int and print_string );

       -when the material for a box has been printed,  call  close_box  ()  to
       close the box;

       -at  the  end  of your routine, flush the pretty-printer to display all
       the remaining material, e.g. evaluate print_newline () .

       The behaviour of pretty-printing commands is unspecified if there is no
       opened  pretty-printing box. Each box opened via one of the open_ func-
       tions below must be closed using close_box for proper formatting.  Oth-
       erwise, some of the material printed in the boxes may not be output, or
       may be formatted incorrectly.

       In case of interactive use, the system  closes  all  opened  boxes  and
       flushes  all  pending  text  (as with the print_newline function) after
       each phrase. Each phrase is therefore executed in the initial state  of
       the pretty-printer.

       Warning:  the  material output by the following functions is delayed in
       the pretty-printer queue in order to compute the proper line  breaking.
       Hence,  you should not mix calls to the printing functions of the basic
       I/O system with calls to the  functions  of  this  module:  this  could
       result  in  some strange output seemingly unrelated with the evaluation
       order of printing commands.








       === Boxes ===



       val open_box : int -> unit


       open_box d opens a new pretty-printing box with offset d .  This box is
       the  general purpose pretty-printing box.  Material in this box is dis-
       played 'horizontal or vertical': break hints inside the box may lead to
       a new line, if there is no more room on the line to print the remainder
       of the box, or if a new line may lead to a new indentation (demonstrat-
       ing  the  indentation  of  the box).  When a new line is printed in the
       box, d is added to the current indentation.



       val close_box : unit -> unit

       Closes the most recently opened pretty-printing box.





       === Formatting functions ===



       val print_string : string -> unit


       print_string str prints str in the current box.



       val print_as : int -> string -> unit


       print_as len str prints str in the current box. The pretty-printer for-
       mats str as if it were of length len .



       val print_int : int -> unit

       Prints an integer in the current box.



       val print_float : float -> unit

       Prints a floating point number in the current box.



       val print_char : char -> unit

       Prints a character in the current box.



       val print_bool : bool -> unit

       Prints a boolean in the current box.





       === Break hints ===



       val print_space : unit -> unit


       print_space  ()  is  used to separate items (typically to print a space
       between two words).  It indicates that the line may be  split  at  this
       point. It either prints one space or splits the line.  It is equivalent
       to print_break 1 0 .



       val print_cut : unit -> unit


       print_cut () is used to mark a good break position.  It indicates  that
       the line may be split at this point. It either prints nothing or splits
       the line.  This allows line splitting at  the  current  point,  without
       printing spaces or adding indentation.  It is equivalent to print_break
       0 0 .



       val print_break : int -> int -> unit

       Inserts a break hint in a  pretty-printing  box.   print_break  nspaces
       offset  indicates  that  the  line may be split (a newline character is
       printed) at this point, if the contents of the current box does not fit
       on  the  current  line.   If the line is split at that point, offset is
       added to the current indentation. If the line  is  not  split,  nspaces
       spaces are printed.



       val print_flush : unit -> unit

       Flushes  the pretty printer: all opened boxes are closed, and all pend-
       ing text is displayed.



       val print_newline : unit -> unit

       Equivalent to print_flush followed by a new line.



       val force_newline : unit -> unit

       Forces  a  newline  in  the  current  box.  Not  the  normal   way   of
       pretty-printing, you should prefer break hints.



       val print_if_newline : unit -> unit

       Executes  the  next  formatting  command if the preceding line has just
       been split. Otherwise, ignore the next formatting command.





       === Margin ===



       val set_margin : int -> unit


       set_margin d sets the value of the right margin to d  (in  characters):
       this  value is used to detect line overflows that leads to split lines.
       Nothing happens if d is smaller than 2.  If d is too large,  the  right
       margin  is  set  to the maximum admissible value (which is greater than
       10^9 ).



       val get_margin : unit -> int

       Returns the position of the right margin.





       === Maximum indentation limit ===



       val set_max_indent : int -> unit


       set_max_indent d sets the value of the maximum indentation limit  to  d
       (in  characters): once this limit is reached, boxes are rejected to the
       left, if they do not fit on the current line.  Nothing happens if d  is
       smaller  than  2.   If  d is too large, the limit is set to the maximum
       admissible value (which is greater than 10^9 ).



       val get_max_indent : unit -> int

       Return the value of the maximum indentation limit (in characters).





       === Formatting depth: maximum number of boxes allowed  before  ellipsis
       ===



       val set_max_boxes : int -> unit


       set_max_boxes  max  sets  the  maximum  number  of boxes simultaneously
       opened.  Material inside boxes nested deeper is printed as an  ellipsis
       (more  precisely as the text returned by get_ellipsis_text () ).  Noth-
       ing happens if max is smaller than 2.



       val get_max_boxes : unit -> int

       Returns the maximum number of boxes allowed before ellipsis.



       val over_max_boxes : unit -> bool

       Tests if the maximum number of boxes allowed have already been  opened.





       === Advanced formatting ===



       val open_hbox : unit -> unit


       open_hbox  ()  opens  a new pretty-printing box.  This box is 'horizon-
       tal': the line is not split in this box  (new  lines  may  still  occur
       inside boxes nested deeper).



       val open_vbox : int -> unit


       open_vbox  d  opens a new pretty-printing box with offset d .  This box
       is 'vertical': every break hint inside this box leads to  a  new  line.
       When a new line is printed in the box, d is added to the current inden-
       tation.



       val open_hvbox : int -> unit


       open_hvbox d opens a new pretty-printing box with offset d .  This  box
       is  'horizontal-vertical': it behaves as an 'horizontal' box if it fits
       on a single line, otherwise it behaves as a 'vertical' box.  When a new
       line is printed in the box, d is added to the current indentation.



       val open_hovbox : int -> unit


       open_hovbox d opens a new pretty-printing box with offset d .  This box
       is 'horizontal or vertical': break hints inside this box may lead to  a
       new  line,  if there is no more room on the line to print the remainder
       of the box.  When a new line is printed in the box, d is added  to  the
       current indentation.





       === Tabulations ===



       val open_tbox : unit -> unit

       Opens a tabulation box.



       val close_tbox : unit -> unit

       Closes the most recently opened tabulation box.



       val print_tbreak : int -> int -> unit

       Break  hint  in a tabulation box.  print_tbreak spaces offset moves the
       insertion point to the next tabulation ( spaces  being  added  to  this
       position).   Nothing  occurs if insertion point is already on a tabula-
       tion mark.  If there is no next tabulation on the line, then a  newline
       is printed and the insertion point moves to the first tabulation of the
       box.  If a new line is printed, offset is added to the current indenta-
       tion.



       val set_tab : unit -> unit

       Sets a tabulation mark at the current insertion point.



       val print_tab : unit -> unit


       print_tab () is equivalent to print_tbreak 0 0 .





       === Ellipsis ===



       val set_ellipsis_text : string -> unit

       Set  the text of the ellipsis printed when too many boxes are opened (a
       single dot, .  , by default).



       val get_ellipsis_text : unit -> string

       Return the text of the ellipsis.





       === Semantics Tags ===


       type tag = string







       === Semantics tags (or simply tags) are used to decorate printed  enti-
       ties  for  user's  defined  purposes, e.g. setting font and giving size
       indications for a display device, or marking delimitation of  semantics
       entities  (e.g. HTML or TeX elements or terminal escape sequences).  By
       default, those tags do not influence line breaking calculation: the tag
       'markers'  are  not  considered  as  part of the printing material that
       drives line breaking (in other words, the length of  those  strings  is
       considered  as  zero for line breaking).  Thus, tag handling is in some
       sense transparent to pretty-printing and does not interfere with  usual
       indentation.  Hence,  a  single pretty printing routine can output both
       simple 'verbatim' material or richer decorated output depending on  the
       treatment of tags. By default, tags are not active, hence the output is
       not decorated with tag information. Once set_tags is set to  true,  the
       pretty  printer  engine  honours  tags and decorates the output accord-
       ingly.  When a tag has been opened (or closed), it is both and  succes-
       sively 'printed' and 'marked'. Printing a tag means calling a formatter
       specific function with the name of  the  tag  as  argument:  that  'tag
       printing' function can then print any regular material to the formatter
       (so that this material is enqueued as usual in the formatter queue  for
       further  line-breaking  computation).  Marking a tag means to output an
       arbitrary string (the 'tag marker'), directly into the output device of
       the  formatter.  Hence,  the  formatter specific 'tag marking' function
       must return the tag marker string associated to its tag argument. Being
       flushed  directly  into  the output device of the formatter, tag marker
       strings are not considered as part of the printing material that drives
       line  breaking (in other words, the length of the strings corresponding
       to tag markers is considered as zero for line breaking).  In  addition,
       advanced  users may take advantage of the specificity of tag markers to
       be precisely output when the pretty printer has already  decided  where
       to  break  the  lines, and precisely when the queue is flushed into the
       output device.  In the spirit of HTML tags,  the  default  tag  marking
       functions  output  tags enclosed in < and > : hence, the opening marker
       of tag t is <t> and the closing marker </t>  .   Default  tag  printing
       functions  just do nothing.  Tag marking and tag printing functions are
       user definable and can be set by  calling  set_formatter_tag_functions.
       ===



       val open_tag : tag -> unit


       open_tag  t  opens the tag named t ; the print_open_tag function of the
       formatter is called with t as argument; the tag marker mark_open_tag  t
       will be flushed into the output device of the formatter.



       val close_tag : unit -> unit


       close_tag  () closes the most recently opened tag t .  In addition, the
       print_close_tag function of the formatter is called with t as argument.
       The  marker  mark_close_tag t will be flushed into the output device of
       the formatter.



       val set_tags : bool -> unit


       set_tags b turns on or off the treatment of tags (default is off).



       val set_print_tags : bool -> unit




       val set_mark_tags : bool -> unit


       set_print_tags  b  turns  on  or  off  the  printing  of  tags,   while
       set_mark_tags b turns on or off the output of tag markers.



       val get_print_tags : unit -> bool




       val get_mark_tags : unit -> bool

       Return the current status of tags printing and tags marking.





       === Redirecting the standard formatter output ===



       val set_formatter_out_channel : Pervasives.out_channel -> unit

       Redirect the pretty-printer output to the given channel.  (All the out-
       put functions of the standard formatter are set to the  default  output
       functions printing to the given channel.)



       val  set_formatter_output_functions : (string -> int -> int -> unit) ->
       (unit -> unit) -> unit


       set_formatter_output_functions out flush redirects  the  pretty-printer
       output functions to the functions out and flush .

       The  out function performs all the pretty-printer string output.  It is
       called with a string s , a start position p , and a number  of  charac-
       ters n ; it is supposed to output characters p to p + n - 1 of s .

       The  flush  function  is  called whenever the pretty-printer is flushed
       (via conversion %!  , or pretty-printing indications @?  or  @.   ,  or
       using low level functions print_flush or print_newline ).



       val  get_formatter_output_functions  : unit -> (string -> int -> int ->
       unit) * (unit -> unit)

       Return the current output functions of the pretty-printer.





       === Changing the meaning of standard formatter pretty printing ===





       === The Format module is versatile enough to let you  completely  rede-
       fine the meaning of pretty printing: you may provide your own functions
       to define how to handle indentation, line breaking, and  even  printing
       of all the characters that have to be printed! ===


       type formatter_out_functions = {
        out_string : string -> int -> int -> unit ;
        out_flush : unit -> unit ;
        out_newline : unit -> unit ;
        out_spaces : int -> unit ;
        }





       val set_formatter_out_functions : formatter_out_functions -> unit


       set_formatter_out_functions f Redirect the pretty-printer output to the
       functions f.out_string and  f.out_flush  as  described  in  set_format-
       ter_output_functions  .  In  addition, the pretty-printer function that
       outputs a newline is set to the function f.out_newline and the function
       that outputs indentation spaces is set to the function f.out_spaces .

       This way, you can change the meaning of indentation (which can be some-
       thing else than just printing space characters) and the meaning of  new
       lines opening (which can be connected to any other action needed by the
       application at hand). The two functions f.out_spaces and  f.out_newline
       are  normally  connected  to  f.out_string and f.out_flush : respective
       default values  for  f.out_space  and  f.out_newline  are  f.out_string
       (String.make n ' ') 0 n and f.out_string \n 0 1 .



       val get_formatter_out_functions : unit -> formatter_out_functions

       Return  the  current  output functions of the pretty-printer, including
       line breaking and indentation functions. Useful to record  the  current
       setting and restore it afterwards.





       === Changing the meaning of printing semantics tags ===


       type formatter_tag_functions = {
        mark_open_tag : tag -> string ;
        mark_close_tag : tag -> string ;
        print_open_tag : tag -> unit ;
        print_close_tag : tag -> unit ;
        }


       The  tag  handling functions specific to a formatter: mark versions are
       the 'tag marking' functions that associate a string marker to a tag  in
       order for the pretty-printing engine to flush those markers as 0 length
       tokens in the output device of the formatter.  print versions  are  the
       'tag  printing'  functions that can perform regular printing when a tag
       is closed or opened.



       val set_formatter_tag_functions : formatter_tag_functions -> unit


       set_formatter_tag_functions tag_funs changes the meaning of opening and
       closing tags to use the functions in tag_funs .

       When  opening  a tag name t , the string t is passed to the opening tag
       marking function (the mark_open_tag field of  the  record  tag_funs  ),
       that  must  return  the opening tag marker for that name. When the next
       call to close_tag () happens, the tag name t is sent back to the  clos-
       ing  tag  marking function (the mark_close_tag field of record tag_funs
       ), that must return a closing tag marker for that name.

       The print_ field of the record contains the functions that  are  called
       at  tag opening and tag closing time, to output regular material in the
       pretty-printer queue.



       val get_formatter_tag_functions : unit -> formatter_tag_functions

       Return the current tag functions of the pretty-printer.





       === Multiple formatted output ===


       type formatter


       Abstract data corresponding to a pretty-printer (also called a  format-
       ter) and all its machinery.

       Defining  new  pretty-printers  permits unrelated output of material in
       parallel  on  several  output  channels.   All  the  parameters  of   a
       pretty-printer are local to this pretty-printer: margin, maximum inden-
       tation limit, maximum number of boxes simultaneously opened,  ellipsis,
       and  so  on, are specific to each pretty-printer and may be fixed inde-
       pendently.  Given a Pervasives.out_channel output channel oc  ,  a  new
       formatter writing to that channel is simply obtained by calling format-
       ter_of_out_channel oc .   Alternatively,  the  make_formatter  function
       allocates  a  new formatter with explicit output and flushing functions
       (convenient to output material to strings for instance).



       val formatter_of_out_channel : Pervasives.out_channel -> formatter


       formatter_of_out_channel oc returns a new formatter that writes to  the
       corresponding channel oc .



       val std_formatter : formatter

       The  standard  formatter  used by the formatting functions above. It is
       defined as formatter_of_out_channel stdout .



       val err_formatter : formatter

       A formatter to use with formatting functions below for output to  stan-
       dard error. It is defined as formatter_of_out_channel stderr .



       val formatter_of_buffer : Buffer.t -> formatter


       formatter_of_buffer  b returns a new formatter writing to buffer b . As
       usual, the formatter has to be flushed at the end of  pretty  printing,
       using  pp_print_flush  or pp_print_newline , to display all the pending
       material.



       val stdbuf : Buffer.t

       The string buffer in which str_formatter writes.



       val str_formatter : formatter

       A formatter to use with formatting functions below for  output  to  the
       stdbuf  string buffer.  str_formatter is defined as formatter_of_buffer
       stdbuf .



       val flush_str_formatter : unit -> string

       Returns the material printed with str_formatter , flushes the formatter
       and resets the corresponding buffer.



       val  make_formatter  : (string -> int -> int -> unit) -> (unit -> unit)
       -> formatter


       make_formatter out flush returns a new formatter that writes  according
       to  the  output  function  out  , and the flushing function flush . For
       instance, a formatter to the Pervasives.out_channel oc is  returned  by
       make_formatter (Pervasives.output oc) (fun () -> Pervasives.flush oc) .





       === Basic functions to use with formatters ===



       val pp_open_hbox : formatter -> unit -> unit




       val pp_open_vbox : formatter -> int -> unit




       val pp_open_hvbox : formatter -> int -> unit




       val pp_open_hovbox : formatter -> int -> unit




       val pp_open_box : formatter -> int -> unit




       val pp_close_box : formatter -> unit -> unit




       val pp_open_tag : formatter -> string -> unit




       val pp_close_tag : formatter -> unit -> unit




       val pp_print_string : formatter -> string -> unit




       val pp_print_as : formatter -> int -> string -> unit




       val pp_print_int : formatter -> int -> unit




       val pp_print_float : formatter -> float -> unit




       val pp_print_char : formatter -> char -> unit




       val pp_print_bool : formatter -> bool -> unit




       val pp_print_break : formatter -> int -> int -> unit




       val pp_print_cut : formatter -> unit -> unit




       val pp_print_space : formatter -> unit -> unit




       val pp_force_newline : formatter -> unit -> unit




       val pp_print_flush : formatter -> unit -> unit




       val pp_print_newline : formatter -> unit -> unit




       val pp_print_if_newline : formatter -> unit -> unit




       val pp_open_tbox : formatter -> unit -> unit




       val pp_close_tbox : formatter -> unit -> unit




       val pp_print_tbreak : formatter -> int -> int -> unit




       val pp_set_tab : formatter -> unit -> unit




       val pp_print_tab : formatter -> unit -> unit




       val pp_set_tags : formatter -> bool -> unit




       val pp_set_print_tags : formatter -> bool -> unit




       val pp_set_mark_tags : formatter -> bool -> unit




       val pp_get_print_tags : formatter -> unit -> bool




       val pp_get_mark_tags : formatter -> unit -> bool




       val pp_set_margin : formatter -> int -> unit




       val pp_get_margin : formatter -> unit -> int




       val pp_set_max_indent : formatter -> int -> unit




       val pp_get_max_indent : formatter -> unit -> int




       val pp_set_max_boxes : formatter -> int -> unit




       val pp_get_max_boxes : formatter -> unit -> int




       val pp_over_max_boxes : formatter -> unit -> bool




       val pp_set_ellipsis_text : formatter -> string -> unit




       val pp_get_ellipsis_text : formatter -> unit -> string




       val pp_set_formatter_out_channel : formatter ->  Pervasives.out_channel
       -> unit




       val  pp_set_formatter_output_functions : formatter -> (string -> int ->
       int -> unit) -> (unit -> unit) -> unit




       val pp_get_formatter_output_functions : formatter -> unit -> (string ->
       int -> int -> unit) * (unit -> unit)




       val  pp_set_formatter_tag_functions  : formatter -> formatter_tag_func-
       tions -> unit




       val pp_get_formatter_tag_functions  :  formatter  ->  unit  ->  format-
       ter_tag_functions




       val  pp_set_formatter_out_functions  : formatter -> formatter_out_func-
       tions -> unit




       val pp_get_formatter_out_functions  :  formatter  ->  unit  ->  format-
       ter_out_functions

       These  functions  are  the basic ones: usual functions operating on the
       standard formatter are defined via partial evaluation of  these  primi-
       tives.  For instance, print_string is equal to pp_print_string std_for-
       matter .





       === Convenience formatting functions.  ===



       val pp_print_list : ?pp_sep:(formatter -> unit -> unit)  ->  (formatter
       -> 'a -> unit) -> formatter -> 'a list -> unit


       pp_print_list  ?pp_sep  pp_v ppf l prints the list l .  pp_v is used on
       the elements of l and each element is separated by  a  call  to  pp_sep
       (defaults to Format.pp_print_cut ). Does nothing on empty lists.


       Since 4.02.0



       val pp_print_text : formatter -> string -> unit


       pp_print_text  ppf  s  prints  s  with spaces and newlines respectively
       printed with Format.pp_print_space and Format.pp_force_newline .


       Since 4.02.0





       === printf like functions for pretty-printing.  ===



       val fprintf : formatter -> ('a, formatter, unit)  Pervasives.format  ->
       'a






       ===  fprintf  ff  fmt  arg1 ... argN formats the arguments arg1 to argN
       according to the format string fmt, and outputs the resulting string on
       the  formatter ff.  The format fmt is a character string which contains
       three types of objects: plain characters and conversion  specifications
       as specified in the Printf module, and pretty-printing indications spe-
       cific to the Format module.  The pretty-printing indication  characters
       are  introduced  by a @ character, and their meanings are: - @[: open a
       pretty-printing box. The type and offset of the box may  be  optionally
       specified  with  the  following syntax: the < character, followed by an
       optional box type indication, then an optional integer offset, and  the
       closing  >  character.   Box  type is one of h, v, hv, b, or hov, which
       stand respectively for an horizontal box, a vertical box, an  'horizon-
       tal-vertical'  box,  or an 'horizontal or vertical' box (b standing for
       an 'horizontal or  vertical'  box  demonstrating  indentation  and  hov
       standing  for  a  regular'horizontal  or vertical' box).  For instance,
       @[<hov 2> opens an 'horizontal or vertical' box with indentation  2  as
       obtained  with  open_hovbox  2.   For more details about boxes, see the
       various box opening functions open_*box.  - @]: close the most recently
       opened  pretty-printing  box.   - @,: output a good break hint, as with
       print_cut ().  - @ : output a good break space, as with print_space ().
       -  @;:  output  a  fully  specified good break as with print_break. The
       nspaces and offset parameters of the break may be optionally  specified
       with  the  following  syntax:  the  < character, followed by an integer
       nspaces value, then an integer offset, and a closing >  character.   If
       no  parameters  are  provided,  the good break defaults to a good break
       space.  - @.: flush the pretty printer and output a new line,  as  with
       print_newline  ().   -  @<n>: print the following item as if it were of
       length n.  Hence, printf @<0>%s arg prints arg as a zero length string.
       If @<n> is not followed by a conversion specification, then the follow-
       ing character of the format is printed as if it were of  length  n.   -
       @{:  open  a  tag. The name of the tag may be optionally specified with
       the following syntax: the < character, followed by an  optional  string
       specification, and the closing > character. The string specification is
       any character string that does not contain the closing  character  '>'.
       If  omitted,  the  tag  name  defaults  to  the empty string.  For more
       details about tags, see the functions open_tag and  close_tag.   -  @}:
       close  the most recently opened tag.  - @?: flush the pretty printer as
       with print_flush ().  This is equivalent to the conversion %!.  -  @\n:
       force  a  newline,  as  with  force_newline ().  - @@: print a single @
       character.  Example: printf  @[%s@  %d@]@.  x  =  1  is  equivalent  to
       open_box  (); print_string x = ; print_space (); print_int 1; close_box
       (); print_newline ().  It prints x = 1 within  a  pretty-printing  box.
       Note:  If  you need to prevent the interpretation of a @ character as a
       pretty-printing indication, you can also escape it with a %  character.
       ===



       val printf : ('a, formatter, unit) Pervasives.format -> 'a

       Same as fprintf above, but output on std_formatter .



       val eprintf : ('a, formatter, unit) Pervasives.format -> 'a

       Same as fprintf above, but output on err_formatter .



       val sprintf : ('a, unit, string) Pervasives.format -> 'a

       Same as printf above, but instead of printing on a formatter, returns a
       string containing the result of formatting the  arguments.   Note  that
       the  pretty-printer queue is flushed at the end of each call to sprintf
       .

       In case of multiple and related calls to sprintf to output material  on
       a  single string, you should consider using fprintf with the predefined
       formatter str_formatter and call  flush_str_formatter  ()  to  get  the
       final result.

       Alternatively, you can use Format.fprintf with a formatter writing to a
       buffer of your own: flushing the formatter and the buffer at the end of
       pretty-printing returns the desired string.



       val asprintf : ('a, formatter, unit, string) Pervasives.format4 -> 'a

       Same as printf above, but instead of printing on a formatter, returns a
       string containing the result of formatting the arguments.  The type  of
       asprintf is general enough to interact nicely with %a conversions.


       Since 4.01.0



       val  ifprintf : formatter -> ('a, formatter, unit) Pervasives.format ->
       'a

       Same as fprintf above, but does not print anything.  Useful  to  ignore
       some material when conditionally printing.


       Since 3.10.0





       === Formatted output functions with continuations. ===



       val  kfprintf : (formatter -> 'a) -> formatter -> ('b, formatter, unit,
       'a) Pervasives.format4 -> 'b

       Same as fprintf above, but instead of returning immediately, passes the
       formatter to its first argument at the end of printing.



       val ikfprintf : (formatter -> 'a) -> formatter -> ('b, formatter, unit,
       'a) Pervasives.format4 -> 'b

       Same as kfprintf above, but does not print anything.  Useful to  ignore
       some material when conditionally printing.


       Since 3.12.0



       val ksprintf : (string -> 'a) -> ('b, unit, string, 'a) Pervasives.for-
       mat4 -> 'b

       Same as sprintf above, but instead of returning the string,  passes  it
       to the first argument.





       === Deprecated ===



       val bprintf : Buffer.t -> ('a, formatter, unit) Pervasives.format -> 'a

       Deprecated.  This function is error prone. Do not use it.

       If you need to print to some buffer b , you must first define a format-
       ter  writing  to  b , using let to_b = formatter_of_buffer b ; then use
       regular calls to Format.fprintf on formatter to_b .



       val kprintf : (string -> 'a) -> ('b, unit, string, 'a)  Pervasives.for-
       mat4 -> 'b

       Deprecated.  An alias for ksprintf .



       val  set_all_formatter_output_functions  : out:(string -> int -> int ->
       unit) -> flush:(unit -> unit) -> newline:(unit -> unit) ->  spaces:(int
       -> unit) -> unit

       Deprecated.  Subsumed by set_formatter_out_functions .



       val  get_all_formatter_output_functions : unit -> (string -> int -> int
       -> unit) * (unit -> unit) * (unit -> unit) * (int -> unit)

       Deprecated.  Subsumed by get_formatter_out_functions .



       val pp_set_all_formatter_output_functions : formatter -> out:(string ->
       int  ->  int -> unit) -> flush:(unit -> unit) -> newline:(unit -> unit)
       -> spaces:(int -> unit) -> unit

       Deprecated.  Subsumed by pp_set_formatter_out_functions .



       val  pp_get_all_formatter_output_functions  :  formatter  ->  unit   ->
       (string -> int -> int -> unit) * (unit -> unit) * (unit -> unit) * (int
       -> unit)

       Deprecated.  Subsumed by pp_get_formatter_out_functions .





OCamldoc                          2014-10-18                         Format(3)

ocaml 4.02.1 - Generated Sun Oct 19 09:09:37 CDT 2014
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